In a few weeks the parties to the UN Climate Convention will meet in Lima, Peru to prepare for their Paris meeting in 2015. This is the culmination of a process that began in Durban in  2011 with the aim of securing agreement to reduce greenhouse gas emissions to a level at which there is two-in-three chance of restricting the average global temperature increase to 2 degrees Celsius above the pre-industrial level.

The meeting will take place just about a month after the Intergovernmental Panel on Climate Change released its synthesis report that summarised the outcome of its fifth assessment drafted by over 800 authors and reviewers from 85 countries.  This assessment report is more categorical in asserting that the observed changes are not just a natural fluctuation but a consequence of anthropogenic emissions of greenhouse gases. It is also more insistent on the need for immediate action.

The risks of climate change depend on cumulative emissions. The IPCC synthesis report presents a global carbon budget for containing the likely temperature increase to 2 degrees Celsius above pre-industrial levels. To meet this goal, cumulative emissions would have to be limited to 790 gigatonnes of carbon (GtC) of which we have used up 515 GtC leaving us with 275 GtC. To stay within this budget, global emissions will have to come down by 40-70% of the 2010 level by 2050 and zero by the end of the century.  The negotiations are about how what remains should be shared.

In 1992 when the convention was signed the confrontation was not between North and South but between those who were sceptical about the reality of anthropogenic impact on climate change and those who were convinced that it was sufficiently proven. There was also US-Europe confrontation on burden-sharing. The developing countries were not under any sort of pressure and their demand for common but differentiated responsibility was accepted.

Today, twenty years later the situation is very different. Rapid growth and the heavy dependence on coal has pushed China into the number one position of emitters in the aggregate.  Its per capita emissions are also now at 7.2 tonnes of CO2 comparable to Europe. They are now under pressure to join in the mitigation effort and the first concrete result of this is the recently announced US-China deal where the U.S. has committed to an absolute reduction in emissions of 26-28% relative to 2005 level before 2025 and China has committed to peaking its emissions not later than 2030 and raising the contribution of non-carbon energy sources from the current 10% to 20% of primary energy supply.

The U.S. commitment does involve some additional effort on their side. But China got way easily. Its peaking commitment does not stop it from continuing to increase its emissions to 2030 when they may reach 10-12 tonnes per capita, more or less comparable to the U.S. The doubling of non-carbon energy is a more serious commitment but readily achievable given the way China is pushing solar and wind energy. 

In some ways the most significant element in the deal is that the U.S. has accepted differentiation in the nature of the commitment between the two countries. Differentiation on the basis of capacity or developmental need maybe acceptable to the U.S. Their problem is with differentiation based on culpability for past emissions.

The fact that the two countries which are quite prepared to be in a minority of one in multilateral negotiations have come up with something positive that they can put forward as the "Intended nationally determined contribution" (INCD) will put pressure on others to come up with something credible.,Europe has already raised its commitment to a 40% reduction in emissions by 2030 relative to 1990 levels and raising the share of renewables to 27%. Japan, no doubt will also announce something soon.

This puts India in the cross-hair and we will have to come up with our offer on the mitigation front. Now that China has broken ranks and South Africa and Brazil have always been more willing to accept some obligation, India will be under pressure to offer a credible contribution to the global effort to manage climate risks.

We need not fear this. We cannot make an offer on a peaking year. Our per capita emissions st 1.7 tonnes are way below China and there is no reason to equate us with them. However we have a reasonable story to tell on energy efficiency. We can also offer commitments on renewables that are at least as substantial as China's or Europe's promise. The metric that we should  push is of carbon efficiency per unit of GDP. The report of the Expert Group on a Low Carbon Strategy for Inclusive Growth has outlined a path that could give a 42% improvement  in carbon efficiency by 2030 at a cost of a little over $800 billion dollars of investment. The merit of this offer is that it gives a basis for demanding equally precise commitments from the developed countries on finance and technology.

An offer to contribute to carbon emission mitigation through carbon efficiency gains need not involve a substantial growth penalty. In the medium term it will rely on energy efficiency,  which is desirable in  any case, and renewables, which are fast becoming an attractive proposition in terms of costs. It will also strengthen the case for effective international action on adaptation support, which would be welcome given the substantial adaptation measures we will have to take even if the temperature increase is contained at 2 degrees Celsius.

Uncontrolled climate change will be hugely harmful to India and it is in our national interest to do what it takes to get an effective climate agreement. A failure at Paris in 2015 is not in our national interest. We are justified in emphasising equity and we should insist that it should be a factor in the assessment of the adequacy of the national offers that are put on the table, an assessment which should also take into account developmental needs and capacity.  But we must now match the offers from China, USA and Europe with an offer that looks beyond the 2020 carbon intensity goals that we promised at Copenhagen.